Senior Software Engineer in London

We are looking for a Senior Software Engineer to join our engineering team and take a lead role in designing, building, and evolving our online systems and services. You will work closely with the product team to translate ideas and rapid prototypes into well-considered technical plans, then drive your team to deliver and iterate at pace.

What you’ll do:

• Design, build, and maintain highly scalable web services, APIs, and backend systems that handle real-world production load with reliability and performance.
• Collaborate directly with the product team to evaluate ideas and rapid prototypes, proposing clear technical plans that balance ambition with pragmatism.
• Lead and drive the engineering team through delivery, from sprint planning and technical design through to deployment and post‑release iteration.
• Architect and review solutions across the full stack, ensuring consistency in patterns, quality, and long‑term maintainability.
• Define and uphold engineering standards including code review, testing strategy, CI/CD pipelines, and observability practices.
• Partner with product on rapid iteration cycles, keeping feedback loops short, reducing time‑to‑learn, and enabling the team to move with confidence.
• Proactively identify and address technical debt, performance bottlenecks, and reliability risks before they become problems.
• Contribute to architectural decisions and be a meaningful voice in engineering‑wide discussions around direction, tooling, and process.
• Act as an escalation point for complex technical problems, providing clear thinking and solutions under pressure.
• Champion a culture of psychological safety, continuous learning, and high engineering craft within the team.

What you’ll need to succeed:

Essential requirements:

• Significant hands‑on experience building and operating highly scalable online systems and services in production environments.
• Strong proficiency in designing and building RESTful APIs and microservices architectures — with a deep understanding of trade‑offs in distributed systems.
• Solid experience with multiple data storage paradigms: relational databases (e.g. PostgreSQL, MySQL), NoSQL (e.g. MongoDB, DynamoDB, Redis), and the patterns that make each appropriate in context.
• Proven ability to coach and mentor junior and mid‑level engineers through code reviews, pair programming, technical guidance, and constructive feedback.
• Experience translating ambiguous product ideas or early prototypes into structured technical proposals and delivery plans.
• Demonstrated ability to lead an engineering team through a full delivery cycle — from technical design to release — while maintaining momentum and quality.
• Strong understanding of software engineering fundamentals: algorithms, data structures, system design, testing, and operational concerns (monitoring, alerting, incident response).
• Experience working in an agile, fast‑paced product environment with short iteration cycles and close collaboration between engineering and product teams.
• Excellent communication skills — able to articulate complex technical concepts clearly to both technical and non‑technical stakeholders.
• A track record of pragmatic, outcome‑focused decision‑making: balancing technical rigour with the need to ship and learn quickly.

Desirable requirements:

• Experience designing and consuming gRPC services, including protocol buffer schema design and inter‑service communication patterns.
• Familiarity with event‑driven architectures and messaging systems (e.g. Kafka, RabbitMQ, SQS/SNS).
• Experience with cloud‑native infrastructure and deployment patterns (AWS, GCP, or Azure) including serverless, containerisation (Docker/Kubernetes), and infrastructure‑as‑code.
• Exposure to stream processing or real‑time data pipelines at scale.
• Experience with search technologies such as Elasticsearch or OpenSearch.
• Prior experience in a tech lead or staff engineer capacity, with involvement in cross‑team technical decision making.
• Contribution to open‑source projects, engineering blog posts, or technical community involvement.
• Familiarity with product analytics, feature flagging, and experimentation frameworks to support rapid iteration.
• Experience with security‑by‑design principles and implementing secure coding practices across distributed systems.

Your approach to work:

• Takes ownership without being territorial — you share knowledge freely, help others grow, and care about the success of the whole team, not just your own work.
• Brings clarity to ambiguity — you are comfortable working from a rough idea or prototype and can structure thinking around it without needing a perfect brief.
• Balances speed and quality deliberately — you understand when to move fast and when to slow down, and can make that call with sound reasoning.
• Communicates proactively — you surface blockers early, share progress openly, and keep both your engineering team and product stakeholders informed without being prompted.

Important to know:

• Location: Farringdon, London; Cwmbran, Wales; Haddenham.
• Right to Work: Applicants must already hold a legal right to work in the UK without time restrictions and without the need for future sponsorship. We are unable to provide Skilled Worker visa sponsorship.
• Fintel plc and all the businesses within it adopt a zero‑tolerance approach to discrimination on any of the protected grounds in the Equality Act 2010. We are committed to providing equal opportunities to all current and prospective employees regardless of age, disability, sex, sexual orientation, pregnancy and maternity, race or ethnicity, religion or belief, gender identity, or marriage and civil partnership.
• We aspire to have a diverse workforce because, in our view, diversity enables better business outcomes. We also believe that a more inclusive workplace, where people of different backgrounds work together, ensures better outcomes for all staff. From application to interview, we place inclusion at the heart of all we do.